Identity verification relates to verifying a user's identity by various techniques. Biometrics-based identity verification relates to verifying a user's identity based on the user's fingerprint, iris, etc. Both fingerprints and irises of users are unvarying and unique. “Invariance” relates to the fact that a fingerprint or iris does not undergo change over a long period of time unless the fingerprint or the iris is injured. “Uniqueness” relates to the fact that a fingerprint or iris has a unique pattern. Patterns of fingerprints or irises of different users are different, so that a fingerprint or iris can uniquely indicate a user.
Using fingerprints as an example of existing biometrics-based identity verification, prior registration of the fingerprints is often used. A verification technique is performed each time a user identity is to be verified. The registration process primarily includes: collecting images of user fingerprints via collecting terminals, extracting feature point information from the fingerprints, and storing the extracted feature point information. The feature point information includes feature point types, coordinates, directions, and other such parameters. The feature point types include line pattern endpoints, dots, or loops. During identity verification, a fingerprint of a to-be-verified user is collected via a collecting terminal. The fingerprint of the to-be-verified user undergoes pre-processing and feature point information is extracted. The feature point information of the to-be-verified user is compared with the stored feature point information. When a level of conformity between the feature point information of the to-be-verified user and the stored feature point information reaches a predetermined threshold value, the to-be-verified user is verified.
Under some circumstances, an already registered user has difficulty in having his or her identity verified due to some specific reason, with consequences affecting the user's normal work or life. For example, a collecting terminal is used for too long a time period, so that internal components of the collecting terminal have aged and that the collected images are of a lower quality. Consequently, the extracted feature point information would be incomplete, which results in a level of conformity that fails to reach a predetermined threshold value, making verification of the to-be-verified user difficult. Furthermore, the physical characteristics of some users are insufficiently clear to provide useful biometrics information. For example, the fingerprints of a user may be naturally faint or unclear due to scars, etc. In such a case, the image quality collected by the collecting terminal would be relatively low. Consequently, the extracted feature point information would be incomplete, which results in a level of conformity below the predetermined threshold value, making verification of the to-be-verified user difficult. Under some special situations, such as when skin on a finger is peeling or sweat glands of the finger are over-developed or the iris is inflamed, the user may also find verification difficult. In the above situations, users can experience lower identity verification pass rates, leading to considerable hassles for such users. For example, when a door security system has a fingerprint or iris identification feature, failure of a user's identity to be verified results that the user cannot open the door. In an example of a financial product that uses biometrics to verify user identity, a user failing to have his or her identity verified is not able to buy a desired financial product.